US11105470B2ActiveUtilityA1
Method for determining loss of gas in gas container
Assignee: KOREA RES INST STANDARDS & SCIPriority: Jan 31, 2017Filed: Jan 16, 2018Granted: Aug 31, 2021
Est. expiryJan 31, 2037(~10.6 yrs left)· nominal 20-yr term from priority
G01F 17/00F17C 2260/038F17C 2201/056F17C 2201/058F17C 2250/0621F17C 2260/024F17C 2201/032F17C 13/028F17C 13/02F17C 2201/0109G01F 1/34G01M 3/3263
43
PatentIndex Score
0
Cited by
7
References
14
Claims
Abstract
The present invention relates to a method for determining loss of gas in a gas container. According to an embodiment of the present invention, the method for determining the loss of gas in the gas container is characterized by including the steps of (a) filling a first container ( 10 ) with a component gas and a balance gas, (b) measuring a gas pressure inside the first gas container ( 11 ), (c) allowing the first gas container and a second gas container having an evacuated inside to communicate and performing a first-stage gas pressure split, and (d) measuring a gas pressure inside the second gas container, wherein an amount of the component gas adsorbed inside the gas container is calculated through a difference between a measured value of step (b) and a measured value of step (d) and is determined as an amount of gas loss.
Claims
exact text as granted — not AI-modifiedThe invention claimed is:
1. A method for determining a process gas loss in a gas container, the method comprising the steps of:
(a) filling a component gas and a balance gas into a first gas container;
(b) measuring a gas pressure inside the first gas container;
(c) performing a first gas pressure distribution by allowing the first gas container to communicate with a second gas container having an evacuated inside; and
(d) measuring a gas pressure inside the second gas container, wherein
an amount of the component gas adsorbed inside the first and second gas containers is calculated through a difference between a measured value of step (b) and a measured value of step (d) and is determined as an amount of gas loss,
wherein
only the component gas is adsorbed inside the first gas container and the second gas container, and
the balance gas is not adsorbed inside the first gas container and the second gas container.
2. The method of claim 1 , wherein
the amount of the component gas adsorbed inside the first and second gas containers is determined by converting the difference between the pressure values measured in steps (b) and (c) into the number of moles of the component gas.
3. The method of claim 2 , wherein
when the measured value of step (b) is P m,gas,0 , and the measured value of step (d) is P d,gas,1 , an amount n A,loss,m,0 of the adsorbed component gas is determined from formula (1)
1
2
p
m
,
gas
,
0
-
p
d
,
gas
,
1
=
1
2
Z
A
RT
V
cyl
n
A
,
loss
,
m
,
0
(Z A is a compression factor, R is the gas constant, T is a temperature, and V cyl is a gas container internal volume).
4. The method of claim 1 , wherein
when a manufacturing input amount of the component gas in step (a) is n A,grav,m,0 , and a manufacturing input amount of the balance gas is in step (a) is n B,grav,m,0 , and a measured value of molar fraction of the component gas in step (d) is X A,gas,d,1 , the amount of loss n A,loss,m,1 of the component gas is determined by formula (2)
n
A
,
loss
,
m
,
1
=
1
2
(
n
A
,
grav
,
m
,
0
-
n
B
,
grav
,
m
,
0
x
A
,
gas
,
d
,
1
1
-
x
A
,
gas
,
d
,
1
)
.
5. The method of claim 2 , wherein a pressure loss value exhibited by the adsorption of the component gas inside the first gas container in step (b) is two times a pressure loss value exhibited by the adsorption inside the first gas container and the second gas container after performing the first gas pressure distribution in step (d).
6. The method of claim 1 , wherein
a gas pressure inside the first gas container is measured in step (d) and used as a gas pressure measured value inside the second gas container.
7. The method of claim 1 , wherein
the first gas container and the second gas container are the same.
8. The method of claim 1 , further comprising the steps of:
(e) closing a gap between the first gas container and the second gas container and preparing a vacuum-state third gas container;
(f) performing a second gas distribution by allowing the second gas container to communicate with the third gas container; and
(g) measuring a gas pressure inside the third gas container, wherein
the amount of the component gas adsorbed inside the first and second gas containers may be determined through a difference in the measured value of step (d) and a measured value of step (g).
9. The method of claim 8 , wherein
when the measured value of step (b) is P m,gas,0 , and the measured value of step (d) is P d,gas,1 , an amount n A,loss,m,0 of the adsorbed component gas is determined from formula (3)
1
2
p
d
,
gas
,
1
-
p
gd
,
gas
,
1
=
1
2
Z
A
RT
V
cyl
n
A
,
loss
,
m
,
1
(Z A is a compression factor, R is the gas constant, T is a temperature, and V cyl is a gas container internal volume).
10. The method of claim 8 , wherein
when a manufacturing input amount of the component gas step (a) is n A,grav,m,0 , and a manufacturing input amount of the balance gas is in step (a) is n B,grav,m,0 , and a measured value of molar fraction of the component gas in step (d) is x A,gas,gd,1 , the amount of loss n A,loss,m,1 of the component gas is determined by formula (4)
n
A
,
loss
,
m
,
1
=
(
1
2
)
2
(
n
A
,
grav
,
m
,
0
-
n
B
,
grav
,
m
,
0
x
A
,
gas
,
gd
,
1
1
-
x
A
,
gas
,
gd
,
1
)
.
11. The method of claim 8 , further comprising the steps of,
in a case in which i times of gas pressure distributions are performed by using i+1 gas containers:
(h) closing a gap between an (i−1)th gas container and an ith container and preparing a vacuum-state (i+1)th gas container;
(i) performing an ith gas pressure distribution by allowing the ith gas container to communicate with the (i+1)th gas container; and
(j) measuring a gas pressure inside the (i+1)th gas container, wherein
a difference between a gas pressure measured value of the ith gas container in step (h) and the gas pressure measured value of the (i+1)th gas container in step (j) has a constant value of
1
2
Z
A
RT
V
cyl
n
A
,
loss
,
m
,
1
(Z A is a compression factor, R is the gas constant, T is a temperature, and V cyl is a gas container internal volume).
12. The method of claim 1 , wherein
after performing the first gas pressure distribution, a mole fraction X A,gas,d,1 of the component gas inside the second gas container is calculated by formula (5)
x
A
,
gas
,
d
,
1
=
1
2
n
A
,
grav
,
m
,
0
-
n
A
,
loss
,
m
,
1
1
2
n
A
,
grav
,
m
,
0
-
n
A
,
loss
,
m
,
1
+
1
2
n
B
,
grav
,
m
,
0
[n A,grav,m,0 is an amount (mol) of the component gas injected into the first gas container, and n B,grv,m,0 is an amount (mol) of the balance gas injected into the first gas container in step (a)].
13. The method of claim 1 , further comprising a step of displaying, on a precise pressure measuring apparatus, whether a gas pressure equilibrium between the first gas container and the second gas container is completed between steps (c) and (d).
14. The method of claim 1 , further comprising a step of displaying, on a precise pressure measuring apparatus, whether a temperature equilibrium between the first gas container and the second gas container is completed between steps (c) and (d).Cited by (0)
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